ViralORFeome: an integrated database to generate a versatile collection of viral ORFs

Pellet, J.; Tafforeau, L.; Lucas-Hourani, M.; Navratil, V.; Meyniel, L.; Achaz, G.; Guironnet-Paquet, A.; Aublin-Gex, A.; Caignard, G.; Cassonnet, P.; Chaboud, A.; Chantier, T.; Deloire, A.; Demeret, C.; Le Breton, M.; Neveu, G.; Jacotot, L.; Vaglio, P.; Delmotte, S.; Gautier, C.; Combet, C.; Deleage, G.; Favre, M.; Tangy, F.; Jacob, Y.; Andre, P.; Lotteau, V.; Rabourdin-Combe, C.; Vidalain, P. O.

The number of viral genomic sequences available in public databases has increased exponentially, opening new perspectives to understand genetic basis and functional mechanisms that underlie virus replication, pathogenesis and evolution. In particular, this enabled to establish for each virus a list of potential regulatory and expressed sequences, a framework often referred as the 'parts list' of biological systems (1) . Current investigations aim at understanding how these viral components act upon each other and interact with host macromolecules to carry on viral replication and spreading. To reach such a system view of virus cycles, more functional analyses of viral components are necessary, especially in the field of virus-host molecular interactions (2, 3) . To address this question, a large collection of viral open reading frames (ORFs) established in a recombination-based cloning system allowing their mass transfer into various functional assays would be extremely helpful. Such ORF collections, often referred as 'ORFeomes', have been developed for human and few other organisms and represent great resources to explore protein functions in a large-scale setting (4) (5) (6) (7) (8) (9) . Recombination-based cloning technologies like the Gateway Õ system enable the mass cloning of polymerase chain reaction (PCR)-amplified ORFs into a 'donor' vector to create 'entry' clones. Once entry clones have been established, ORFs can be easily recombined into different 'destination' vectors that allow protein expression. So far, only few viral ORFeomes have been built and they are dedicated to a single virus, arguing that much more needs to be achieved (10) (11) (12) (13) .